The Karlstal rock course predominately consists of medium grained sandstone with a colour spectrum ranging from pale to brick red through to light violet, yet it also has yellow-brown to yellow-white elements too. This distinctive colouring results from a small proportion of iron minerals, such as hematite and limonite, within the rock's structure while the lighter colouring is likely due to secondary discolouration as a result of other dissolved minerals.
Its microscopic constituents, according to GRIMM (1990), are principally quartz and rock fragments (90 - 95%) while feldspar that has been partially kaolinised represents a secondary component. Biotite (mica mineral) as well as tourmaline and zircon can also be observed. The rock's primary binding agent is made of quartz, partially by means of sprouting (secondary growth) rounded quartz grains, alongside elements of kaolin and other iron minerals. The rock has significant porosity that is for most parts uniformly distributed throughout the rock course.